K 00546 is a potent inhibitor of cellular cyclin kinases (CDK1 and CDK2) and CDC2-like kinases (CLK1 and CLK3) used in the study of cancer and immune-related diseases.

Calmodulin kinase:8.9 μM, Casein kinase-1:2.8 μM, ERK2:1.0 μM, CLK3:29.2 nM, CDK1-CyclinB:0.6 nM, PKA:5.2 μM, PDGFRβ:1.6 μM, VEGFR2:0.032 μM, CLK1:8.9 nM, CDK2-CyclinA:0.5 nM, GSK-3:0.14 μM

K 00546 binds to the SLK ATP binding site and forms three hydrogen bonds with the kinase hinge residues E109 and C111. In addition, the aminosulfonyl portion of K 00546 interacts with the backbone of L40. [1]
K 00546 also inhibits a number of kinases, including PKA, casein kinase-1, MAP kinase (ERK-2), calmodulin kinase, VEGF-R2, GSK-3, and PDGF-Rβ, with IC50 values of 5.2 μM, 2.8 μM, 1.0 μM, 8.9 μM, 0.032 μM, 0.14 μM, and 1.6 μM, respectively.
K 00546 is a potent CDK1 and CDK2 inhibitor with IC50 values of 0.6 nM for CDK1/cyclin B and 0.5 nM for CDK2/cyclin A. [2]
K 00546 has also been shown to be a potent CDC2-like kinase 1 (CLK1) and CLK3 inhibitor with IC50 values of 8.9 nM and 29.2 nM, respectively. [3]